$A$ water film is formed between two straight parallel wires,each of length $10 \text{ cm}$,kept at a separation of $0.5 \text{ cm}$. Now,the separation between them is increased by $1 \text{ mm}$ without breaking the water film. The work done for this is (surface tension of water $= 7.2 \times 10^{-2} \text{ N/m}$)

• A
  $7.22 \times 10^{-6} \text{ J}$
• B
  $5.76 \times 10^{-5} \text{ J}$
• C
  $1.44 \times 10^{-5} \text{ J}$
• D
  $2.88 \times 10^{-5} \text{ J}$